NetSight
medium4.3

CVE-2026-3636

Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to sanitize team member data when returned via API to users …

Impact

Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to sanitize team member data when returned via API to users without elevated permissions which allows a user without permissions to get data about team members roles via invoking various team API endpoints.. Mattermost Advisory ID: MMSA-2026-00626

Affected packages

EcosystemPackageAffectedFixed in
gogithub.com/mattermost/mattermost-server= 11.6.011.6.1

Affected products

VendorProductAffected versions
MattermostMattermost Server
from 10.11.0 before 10.11.15
from 11.4.0 before 11.4.5
from 11.5.0 before 11.5.4
from 11.6.0 before 11.6.1

Weakness classification

References